This research program investigates the role of phonology in reading English: Does reading a word consist solely of a direct association of grapheme (letters) and meaning, or, instead, is it constrained by phonological information, assembled by mapping letters into phonemes? Despite much research effort addressing whether phonology constrains reading, the existing literature reveals some marked contradictions. These contradictions are largely due to a failure to address the question of what phonology is: Phonological representations assembled in reading are linguistic entities whose processing is constrained by their structure. Thus, any account for the role of phonology must be formulated with reference to its linguistic structure. Two major long term goals motivate the present research program. One is to examine a specific model of the assembly of phonology and its contribution to skilled English readers. According to the two cycles model, consonants and vowels are two distinct structural components assembled by distinct processes that contrast in their speed and automaticity. A series of masking and priming experiments is designed to assess the model's predictions regarding the computations properties of consonant and vowel assembly and it role in reading English. A second broad goal is to investigate the thesis that phonological representations assembled in reading are constrained by linguistic knowledge. Following linguistic theory, this project identifies several manifestations of a structural distinction between consonants and vowels in phonological representations. A series of studies examines whether these linguistic distinctions constrain the structure of the representations assembled in reading. This investigation carries wide interdisciplinary implications. Revealing the nature of assembled phonology and its contribution to skilled reading has direct implications for reading instructions and the study of reading disability. Studying the structure of phonological representations assembledin reading is of great interest to both psycholinguistics and linguistic theory. Most importantly, examining the interaction of reading ability and linguistic phonological competence is not only crucial of our understanding of reading but further has some direct implications for human health: in view of the heritable aspect of the phonological component in reading, investigating the role of phonological representations in reading and their structure explores a component of the human genetic endowment.